It has long been known that intermittently flashing lights attract more attention than lights that illuminate constantly. This is particularly true in automobiles where currently, the turn indicating lights in both the front and back flash intermittently to warn and alert drivers of an impending left or right turn. However, even though flashing lights are more noticeable, they are not employed with vehicle brake lights. The brake lights in current use, conventionally remain continuously illuminated as long as the brake light switch remains closed by the continuous pressure applied to the brake pedal.
The conventional brake light circuit which operates a pair of lights located at the rear of a vehicle has in many instances failed to produce adequate warning. This problem is especially prevalent on newer vehicles that have a large assemblage of lights on the rear panel of the vehicle. In addition, turn signals which are normally located in the same light assembly with the taillights and stoplight often add to the confusion as to whether brakes are being applied or a turn is to be made.
One of the problems in driving is that to drive safely, a driver needs to know how quickly the automobile in front is slowing down with conventional brake lights, an illuminated light only-means that the driver has his or her foot on the brake pedal. The trailing driver does not know if the vehicle is decelerating slowly or whether a sudden panic stop is about to take place. The brake light used in conventional vehicles looks the same in either case.
With vehicles traveling at high speeds on interstate and freeway road systems with relatively little spacing between vehicles; the ambiguity in brake lights can and has caused rear end collisions with consequent vehicular damage, human injury, loss of life and further road congestion.
A search of the prior art did not disclose any patents that read directly on the claims of the instant invention however, the following U.S. patents were considered related:
______________________________________ U.S. PAT. NO. INVENTOR ISSUED ______________________________________ 5,059,947 Chen 22 October 1991 4,663,609 Rosario 5 May 1987 3,593,278 Bower 13 July 1971 3,528,056 Voevodsky 8 September 1970 ______________________________________
U.S. Pat. No. 5,059,947 issued to Chen, discloses a vehicle brake warning device for use in a vehicle with a brake pedal. The device includes a detector for producing different electrical signals in response to the magnitude of the inertia force experienced during braking. Whenever a pressing force is exerted on the brake pedal, the detector experiences an inertia force whose magnitude depends upon the speed of the vehicle. The detector sends an appropriate signal dependent upon the magnitude of the inertia force to a control circuit which then activates a warning device which activates the brake lights.
U.S. Pat. No. 4,663,609 issued to Rosario discloses a brake light warning system for a motor vehicle which causes the brake lights to flash in a manner to attract the attention of a driver to the rear of the vehicle. The system provides a warning of a slow down or stopping of the vehicle upon the application of the brakes. The brake lights are first caused to flash rapidly for 2 or 3 times for a first interval of time followed by prolonged "on" periods interrupted periodically by a short "off" period followed by a short "on" period followed by a short "off" period for a second interval of time as long as pressure is applied to the brake pedal of the vehicle.
U.S. Pat. No. 3,593,278 issued to Bower discloses a vehicle brake light system wherein a flashing signal of variable frequency indicates the rate of deceleration of a vehicle. The system includes a series of inertia switches and resistors forming a decelerometer, a multivibrator and a transistorized gate circuit which flashes the brake lights at a frequency proportional to the detected rate of deceleration.
U.S. Pat. No. 3,528,056 issued to Voevodsky discloses a device for measuring the deceleration of a leading vehicle. The device uses an accelerometer formed by mercury switches tilted at different angles with respect to a horizontal. They are progressively closed as the deceleration increases. In another form, deceleration is measured by brake pressure and in still another form a tachometer device is coupled to a rotating part of the automobile. The warning light, mounted on the leading car, is flashed at a rate which varies exponentially with a component of deceleration.
For background purposes and as indicative of the art to which the invention relates, reference may be made to the following remaining patents found in the search:
______________________________________ U.S. PAT. NO. INVENTOR ISSUED ______________________________________ 4,983,953 Page 8 January 1991 4,403,210 Sullivan 6 September 1983 3,559,164 Bancroft 26 January 1971 3,382,405 Johnson 7 May 1968 ______________________________________